2003 Suburban No Start - Electrical???
 

Hello All! I am new to this forum and first time poster. I have a 2003 Suburban 5.3l no aftermarket anything. I am trying to figure out exactly what is going on with my burb. Story: I ran errands all morning last week and got home around noon. I parked it in reverse in the driveway. I jumped in it around 7pm that same day. Cranked it up and it ran for about two seconds then shut off. Tried desperately to start it and nothing happened. No turning over of the engine. All I hear is the sound in the throttle body and maybe some clicking of the relays coming from underneath the hood. I tried to jump start it, but nothing. So, basically, when I turn the key nothing happens.
What I have checked so far:

1. Battery tested and checked out ok. (Autozone)
2. Checked all the fuses under hood and inside fuse panel. All are good.
3. Hooked up my scan tool, but now it says it cannot communicate with vehicle.
4. Inspected and removed the ground wire (black/yellow) from the rear of engine (passenger side) and grounded it with the main braided ground wire on the firewall.
5. Swapped out relays under hood. (Starter)
6. Tested current coming to starter solenoid 12v. Good.
7. Tested S at solenoid (when key is turned to start vehicle). No power.
8. Hooked up remote starter switch from S at solenoid to battery positive. Turned the key to run and hit the switch. Turned over, but no start.
9. Checked power going to neutral safety switch with test light. Yellow and Red wires (connector side) turn the test light on when ignition is turned to ON.
10. Replaced neutral safety switch. Same problem… no crank.

I am not sure what to check next? PCM? Is there a fuse somewhere I may be overlooking? I thought perhaps the solenoid may be shot, but I should still get power going down the S stud when I turn the key to ON, correct? Also, I don’t know if the passlock theft system is preventing it from turning over? I don’t hear the fuel pump kick on when I turn the key. Also, the chime sometimes stays on when I remove the key from the ignition. This is not an intermittent problem; it simply has not turned back on. If anyone has any ideas I welcome them! This thing is driving me nuts! :dohh::dohh:

Rivas

Re: 2003 Suburban No Start - Electrical???
 

Alright, so after all that. I gave up and took it in to get it checked out. The fuel pump went out. BUT, they also said a fuse kept burning up because of the fuel pump (not sure which fuse it was). So, I would have never been able to figure it out. She is running like a champ now.

Re: 2003 Suburban No Start - Electrical???
 

I'm not buying the fuel pump as being bad. It has it's own fuse "down stream" from all other circuits. It sounds like one of the maxi fuses blew and they mis-diagnosed it then covered their tracks.

Re: 2003 Suburban No Start - Electrical???
 

I did the diagnostic on Rivas Suburban, The Fuel Pump relay & PCM are on the same fuse (PCM-B fuse), The fuel pump was shorted, Blowing the PCM-B fuse & shutting down the PCM, No crank, No SES, No communication with PCM.

This truck has no fuse downstream from the relay, I found it odd as well.

Re: 2003 Suburban No Start - Electrical???
 

OK, cool. I was wrong in thinking it was done by some no-mind shop. Add in the fact I was at home and not near an AllData source. I've seen some scrupulous work done and it torques me off. I'm glad to hear proper diagnostics were done this time

My fear was that something like an ignition switch wiring issue from a botched remote start install or etc.

Re: 2003 Suburban No Start - Electrical???
 

They do good work down there. I just hope this thread will help someone in THEIR diagnosis. I thought I would have been able to figure this issue out on my own, but decided I had wasted enough time on it. They're called professionals for a reason, right?

Re: 2003 Suburban No Start - Electrical???
 

yes, we are

If you have any other problems feel free to ask for help